Johnny Cash, legendary country singer of Folsom Prison Blues, hid a secret from his fans for years according to reports. In the Johnny Cash affair, June Carter found herself in an awkward position -- the Lake of Fire singer got June Carter's sister Anita pregnant!

After the Johnny Cash affair, June's sister Anita agreed to abort the child to spare her sister the embarrassment.

According to ContactMusic, a friend of Johnny Cash and June Carter refused to reveal the secret affair while the couple were living, but has since come forward to the National Enquirer following Cash's death in September 2003.

Watch Johnny Cash Walk the Line here:

The source says, "Anita often toured with John and there was little doubt she was his lover - it wasn't rare for staff members to run into them together in hotel rooms.

"In the 1970s, Anita eventually got pregnant by John and had an abortion. June eventually found out about it."

The insider witnessed when Anita begged June Carter for forgiveness from her deathbed in 1999.

They adds, "Anita died with a broken heart, knowing she had betrayed June and aborted her child."